Electric incubator.



fnnwrnn. sorronna, or COLUMBIA, MISSOURI.

' ELECTRIC iucusa'ron.

Specification of Letters Pass-mt.

Patented June 6, 1911.

Application'filed September 13, 1909. Serial No. 517,397.

To all whom it may concern: I

Be it known that I, EDWIN H. SCHORER, a citizen of the United States,residing at" Columbia, Boone county, State of Missouri,

.5 have invented certain new and useful Improvements in ElectricIncubators, of which the following is a specification. I

This invention relates to the automatic regulation of heat andparticularly to the in regulation of heat developed from an electriccurrent. i

In the transmission, regulation and control of 'a current for theheating of any given s'pace, 'many roblems are involved both in'themaintaining of the temperature "desired and in the economic operation ofthe system as -'a whole.

One of the fields in which'the require- ..ments for thermal regulationhave been most '20- idifiicult to meet has been that ofincubation.

The requirements.ofthis branch are socharacterist'ic and present sofully the general "problems-that the present application .will treatthe; subject more from the general -25. standpoint of incubation inorder that a more complete understandin of the system may be hadalthough it wilIbe understood .that' the features of my invention applyto almost every form of thermal regulation. as, j Exact as are therequirements of general incubation it is within the realm ofbacteriological. incubation that we find the greatest niceties.observed, and the greatest exactness sought. Various incubators havebeen produced and even electrically heated incubators have been triedbut for scientific work an accuracy of incubation-is required which theincubatorusually found in laboratories fails to devleop, especially inthe work 40 with certain, micro-organisms which grow only within certainnarrow limits of temperature variation- In'such work it is ab-j solutelyessential that the incubator. retain a constant temperature throughoutthe de- 'velopment of the culture.

In my present invention, which as I have before stated is of generalapplication, I have devised a system and means formaking allow-, anceforthe varying conditions of external temperature as well as for the promptand exact adjustment andreadjustment of the heat development to theinternal temperature desired. This allowance for external temperaturechanges makes itpossible td keep an incubator wherever desired. ratherthan necessitating its location in the cellar aslis so often the casewhere the thermostatic adjustment has not been able to accommodate thevarying temperatures of a room or laboratory which in the winter monthssometimes show differences in twenty-four hours of 30 F. For such avariation as i this the ordinary thermostat is not and can not generallybe adjusted.

In general my system involves the use of means for varying the amount ofelectrical energy delivered to the heater in accordance with the generalor external temperature and in the graduation of such supply as thelimit of variation is approached in either direction. The features of mythermostats and the use therein of an expansile contact breaker, in theform and arrangements of the parts and in the various details, will bemore fully set forth in the specification which follows.

Throughout these specifications and in the.

drawings which form a part thereof I have employed like referencenumerals, corres'pondingly assignedto like parts for their indication.for the most part it is believed that they .fully show the invention andwill readily enable anyone skilled in'th-e art to carry out theinvention involved. In these drawings I have shown several forms of, myin- .vention as illustrative of its scope application and use.

In the various figures shown :-Figure 1 Y is a diagrammatic showing ofan incubator chamber with an internal thermostat and an external pilot,Fig. 2, a similar View of incandescent radiation with plural bulbs Whilediagrammatic in form and a modified contact breaker, Fig. 3, an

arrangementfor a system on-high voltage, showing resistance and solenoidinterruption, Fig. 4 shows a system with an external subcontrol foraccommodation to atmospheric variations, and Fig. 5 indicates a systemin which a differentiated thermal set follows and regulates ingraduation. V

In .the figures the parts in common are an indicated chamber or space 1in which is-located a radiator indicated either as a heater coil 2 oran-incandescent lamp 3' I ing differential expansion thermostatically;

6 a rheostat and 7 an electric magnet contact control.

8 is any's'ource of electrical energy that the dynamo 8 supplies currentthrough the lines 9 and 10 to a heater coil 2 when, and. as long as, thethermostat has its points in contact. During this time the pilot light11 is illuminated. As soon however as the temperature above thepredetermined point the oppositely faced hook points of a are separatedan?! the contact is broken cutting oit the heat generation and. thepilotlight. The same general arrangement is had in Fig. 2, incam escentlamps 3 in parallel, however, being shown and the spiral thermostat 5being substituted for my preferred contacts at.

Fig. 3 is intended to illustrate. a form or arrangement. where a highcurrent is used. In it the Sparking of the contact is avoided byemploying an electric magnet 7 to close the circuit 9, 10, said electricmagnet being located. in a. shunt 11 in which is placed a thermostat iand a resistance In Fig. i I have illustrated how an incubator may beregulated with regard to that very important factor, 1'. 6., the external temperature. The line 9, in which is located the contact 1, isdivided into 9 and 9 and the heater coils 2- and 2" are wound one intoeach. The branch 9 is carried outside the incubator and at some external point the contact t is located. The contacts 4 and 4 arethermally dilierentiated, for example i being operable at say F. whileat would be set for say 100 F. Thus during the. day when heat is on inthe laboratory the contact P would remain open but when the temperatureof the laboratory fell below 65 F. the contact would close and theradiator 2 would be cut in, thus afifording an increased surface to keepup the temperature of theincubator in spite of the cooler externalsurroundings.

In Fig. 5 I have shown a thermal series which I have indicated 43, 4, 4set for say 65 and 60 F. respectively. These are also respectively inbranches 9 9 and 9, in each of which a heater coil is wound and allconnected to the return wire 10.

The operation of this system would be as follows: As the temperaturerose to 60 contact 4 would be expanded to cut out the radiator 2 At 65the heater coils 2 would be out out, thus reducing the radiationgradually till at 70 the heater coil 2 would be cut out and in as longas conditions remained nearly constant.

It will be readily seen that the two forms last described are readilycapable of use together if it be desired to secure a graduatedgeneration externally, internally or both. I The points of the hook tipsare platinum and the members of: suitable conductive expansile metal.The various forms shown are capablc'o't' a great variety of combinationsto meetditi'erent requinmients and it is to be understood that the useof one or more than one of the teaturr been in any figure insubstitution for a part of another figure or in addition theretocontemplated.

Various modifications may of course be made within the limits of theappended claims in the various arrangenwnts and constructions of theparts all witlnult departing from the spirit of my invention.

Various metals may o't cour be used for the members of the thermalcircuit cloriiure, it only being necessary that the meal be a. properelectric conductor andv have suitable expansile properties. It is to benoted that the conductor is operative in contracted position in which itis at its best conductive condition and, therefore at its: greatestefficiency and less likely to heat and expand on account of its ownresistance.

his makes the device more delicate as a thermostat and more eflicient asa conductor.

\Vhat I therefore t m and t cure by Letters Pater )8 1. An incubatorcrm'xprisiug a ciunnber casing, a plurality of electric radiatorsinfluentially associated therewith, an electric circuit for eachradiator and a pair out thermally separable contacts in each or saidcircuits, said pairs of contacts being therrmilly differentiated fromeach other.

2. An incubator conuorising a. chamber casing, means for heating saidcasing, thermal means within said chamber for absolutely governing thetemperature of said chamber and thermal means located externally of saidchamber for partially governing said heating means, said means beingthermally differentiated.

3. An incubator comprising a chamber casing, an electric radiatorintiuentialty associated with said. chamber, a pair oi' thermallyseparable contacts within said chamber and inthe circuit of saidradiator and a pair of thermally separable contacts mounted externallyof said chamber and also in circuit with said radiator said pairs of contacts being adjusted whereby said circuits will be absolutely governedby said internal thermal means and partially governed by said externalthermal means.

In testimony whereof I afi'ix my signature in presence of two witnesses.

1. e LO :5-

Witnesses:

ELLIS Simian, J11, EDWARD N. (iconic.

